Decorative faceplates for light switches and dimmers have generally been mounted via two widely used designs. One design involves using a common two-screw faceplate where the attachment screws extend through the faceplate and into threaded holes in the electrical switch or dimmer's metal yoke plate. The screw heads are visible and are therefore typically pre-painted by the faceplate manufacturer to match the color of the faceplate. A second type of design involves using a “screwless” two-piece faceplate and sub-plate system. In this second design, a non-visible sub-plate is typically attached to the yoke plate utilizing the yoke plate's threaded holes that would normally be used to mount the common two-screw faceplate. Then these screws are hidden when the decorative screwless faceplate is snapped onto the sub-plate through some proprietary mating system.
Prior two-piece mating systems tend to use either 1) multiple slots on a sub-plate with corresponding snaps that lock into the slots, or 2) knife edges on the top and bottom of the sub-plate, with corresponding grooves on the faceplate that together create a “ratcheting” mechanism. Such snap systems work for mounting faceplates, but tend to rattle, which can reduce its appeal from the customers' perspective. Further, the snap system typically accommodates just one faceplate mounting depth in relation to the wall.
The ratcheting system improves on the snap system because it tends to rattle less and allows for different mounting depths in relation to the wall due to its parallel-spaced ratchet grooves, but the sub-frame can be fragile and easily broken upon repeated removal and attachment.